Scroll machines, such as scroll compressors using a fixed scroll and an orbiting scroll housed within a compressor shell, are well known in the industry. Each of the scrolls of a scroll compressor has a spiral wrap extending axially from a base plate. The spiral wraps nest with one another to form pockets of varying volume. A fluid introduced at a low pressure into a pocket is compressed by the cooperating movement of the spiral wraps progressively decreasing the volume of the pocket. The compressed gas is discharged from a high pressure area proximate the center of the wraps. The fixed scroll is typically bolted to a crankcase which has a bearing surface upon which the orbiting scroll orbits. A motor drives a crankshaft which in turn drives the orbiting scroll along its orbital path, typically via a compliant bushing, or slider block. A lubricant is typically introduced to the bearing surfaces of the compressor to reduce the friction incurred by the relative movement of the components of the compressor. The various components of the scroll machines must be precisely positioned within the shell in order to properly align the scroll wraps and other mating surfaces, a task which can be difficult to accomplish. In assembly of a typical scroll machine, for example, expensive positioning equipment is used to align the fixed scroll and the crankcase before they are bolted together.
U.S. Pat. No. 4,522,575 to Tischer et al. discloses a radially outer edge of a frame being fixed between upper and lower shells of a scroll type machine. A stationary scroll is housed within the compressor above the frame and is connected only to the frame.
U.S. Pat. No. 5,064,356 to Horn discloses a scroll type machine having a cap welded to a shell with a partition extending transversely below the cap, the cap and partition defining a muffler chamber. The partition must be properly positioned before it is welded in place.
It is an object of the present invention to provide a scroll compressor with an improved assembly which reduces or wholly overcomes some or all of the aforesaid difficulties inherent in prior known devices. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of certain preferred embodiments.